I'm looking for a no or low VOC varnish or suitable product to seal a pine farm table.

Answer

The history of finishes is an interesting example of the green revolution.

Our ancestors initially developed finishes from plant, animal and fish oils. Linseed and tung oil are examples of plant oils with fish oils, at one time protecting the exterior shingles of early New England homes.

With the Industrial Revolution, finishes were then developed from petroleum, a non-renewable resource.

We are now reevaluating these solutions and returning to plant oils and other renewable resources.

Drying oils, such as linseed or tung oil, are now gaining popularity.Tung oil, made from a pressed seed from the Tung tree, is preferred over linseed oil which darkens over time and is susceptible to mold.

Water-based first-generation sustainable finishes are being replaced with plant oils and protein-based finishes, whose properties make for more durable finishes.

Selecting a nontoxic finish today

In selecting a nontoxic finish today, one should be aware of the amount of VOCs (volatile organic compounds) in the finish which when offgassed will impact the indoor air quality. When evaporated into the air, VOCs contribute to smog and can create health problems when inhaled in excess.

VOCs come from manmade as well as natural materials, and a durable finish made of plant oils or protein will have some VOCs as these compounds add to its strength.

Petroleum-based finishes have harmful levels of these VOCs which are apparent by their noxious smell.

Codes now mandate the amount of VOCs allowable, with the most stringent in the U.S. being California’s, which limits VOC levels to 250g/L.

Made from agricultural waste

There is now a multitude of products that have replaced petroleum-based finishes including products made from agricultural waste materials.

Vermont Natural Coatings is a finish made from the protein found in whey, a byproduct of the production of cheese. Reformulated as Polywhey, what was a pollutant is taken out of the waste stream and given a new purpose.

Vermont Natural Coatings was first developed as a furniture finish, but given its hard surface, is also used as a floor finish.

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